Inerted plate dryer and method of drying solvent based coating
View Patent ↗An inerted plate dryer for drying solvent based coating is disclosed. The dryer uses two tiers of substantially parallel heating plates that are located not more than 10 cm apart. A moving web with solvent based coating is passed through the dryer, and runs closer to one of the heating plates. The method of using such inerted plate dryer is also disclosed.
1. An apparatus for drying, curing, or deaerating a continuous moving web carrying a liquid layer, comprising:
a housing enclosing a drying chamber, said housing having entry and exit slots through which said web may be passing through said chamber; said entry and exit slots having a sealing mechanism to prevent leakage of ambient air into the drying chamber, or leaking out of the gas stream from the chamber into the ambient;
a bottom heated plate and a top heated plate aligned substantially parallel to each other with a space between them, said space is no more than 10 cm distance apart;
the web that carries a liquid layer is located less than 20 mm from the bottom heated plate;
at least one inlet for a gas stream to flow into the chamber with a velocity, said velocity is between 2 m/s and 20 m/s;
at least one outlet for an exhaust to flow out of the chamber, wherein the carrier web is closer to the bottom plate than to the top plate;
wherein the apparatus is used as first drying zone, ahead of a conventional oven;
wherein a fraction of a solvent laden stream that circulates between the heated plates of the apparatus is fed to the exit seal as impinging seal(s);
where the gas released by the exit seal is captured by a draft of an upstream conventional dryer which entrance is kept at sub-atmospheric pressure.